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        <h1>如何优化Tomcat的性能以应对高并发场景？ - 学习卡片</h1>
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          <div class="card-category">配置</div>
          <div class="card-question">在操作系统层面优化Tomcat时，有哪些关键的配置可以调整以提高并发处理能力？</div>
          <div class="card-footer">点击卡片查看答案</div>
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          <div class="card-category">配置</div>
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            <div class="card-answer">可以调整文件句柄限制（如 `ulimit -n 65536`），优化内核TCP设置（如 `net.core.somaxconn` 和 `net.ipv4.tcp_tw_reuse`），以及关闭或调整交换空间（Swap）来避免因内存分页导致的性能下降。</div>
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          <div class="card-source">来源: 2. 操作系统级别的优化</div>
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          <div class="card-category">调优</div>
          <div class="card-question">在进行JVM调优时，为何推荐将初始堆大小(-Xms)和最大堆大小(-Xmx)设置为相同的值？</div>
          <div class="card-footer">点击卡片查看答案</div>
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          <div class="card-category">调优</div>
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            <div class="card-answer">将初始堆大小和最大堆大小设置为相同的值（例如 `-Xms4g -Xmx4g`），可以减少JVM在运行时进行堆内存动态扩展所带来的开销。</div>
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          <div class="card-source">来源: 3. JVM 调优</div>
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          <div class="card-category">配置</div>
          <div class="card-question">在Tomcat的线程池配置中，`maxThreads` 和 `acceptCount` 这两个核心参数分别有什么作用？</div>
          <div class="card-footer">点击卡片查看答案</div>
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          <div class="card-category">配置</div>
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            <div class="card-answer">`maxThreads` 是最大工作线程数，它设置了服务器能够处理的最大并发请求数量。`acceptCount` 是当所有工作线程都在处理请求时，能够进入等待队列的最大请求数。</div>
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          <div class="card-source">来源: 4. Tomcat 配置优化</div>
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          <div class="card-category">特性</div>
          <div class="card-question">为什么文档推荐在Tomcat中启用NIO（非阻塞 I/O）连接器？</div>
          <div class="card-footer">点击卡片查看答案</div>
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          <div class="card-category">特性</div>
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            <div class="card-answer">文档推荐使用NIO（非阻塞 I/O）连接器，因为它可以提升服务器处理并发连接的性能。</div>
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          <div class="card-source">来源: 4. Tomcat 配置优化</div>
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          <div class="card-category">实践</div>
          <div class="card-question">除了调整Tomcat本身，应用程序层面有哪些优化措施可以提升整体性能？</div>
          <div class="card-footer">点击卡片查看答案</div>
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          <div class="card-category">实践</div>
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            <div class="card-answer">应用程序层面的优化措施包括：优化代码和SQL查询以减少资源消耗、优化会话管理（减少数据大小和数量）、以及调整数据库连接池配置以确保连接的高效利用。</div>
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          <div class="card-source">来源: 5. 应用程序优化</div>
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          <div class="card-category">架构</div>
          <div class="card-question">当单个Tomcat节点负载过高时，文档提到了哪两种主要的架构级解决方案？</div>
          <div class="card-footer">点击卡片查看答案</div>
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          <div class="card-category">架构</div>
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            <div class="card-answer">文档提到了两种主要方案：1) 使用硬件或软件负载均衡器（如 Nginx、HAProxy）来分发请求；2) 部署Tomcat集群以提高可用性和负载能力。</div>
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          <div class="card-source">来源: 6. 负载均衡和集群</div>
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          <div class="card-category">特性</div>
          <div class="card-question">在Tomcat中启用GZIP压缩有什么主要好处，并且如何配置它？</div>
          <div class="card-footer">点击卡片查看答案</div>
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          <div class="card-category">特性</div>
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            <div class="card-answer">主要好处是减少网络传输的数据量，从而提高带宽利用率。可以通过在Connector配置中设置 `compression="on"` 并指定 `compressableMimeType` 等参数来启用。</div>
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          <div class="card-source">来源: 7. 启用 GZIP 压缩</div>
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          <div class="card-category">硬件</div>
          <div class="card-question">对于I/O密集型的Web应用，在硬件层面有什么具体的优化建议可以提升Tomcat性能？</div>
          <div class="card-footer">点击卡片查看答案</div>
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          <div class="card-category">硬件</div>
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            <div class="card-answer">对于I/O密集型应用，建议使用SSD（固态硬盘）来提升磁盘的读写速度。</div>
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          <div class="card-source">来源: 1. 硬件资源优化</div>
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          <div class="card-category">工具</div>
          <div class="card-question">为了及时发现并定位Tomcat的性能瓶颈，文档推荐了哪些监控工具或技术？</div>
          <div class="card-footer">点击卡片查看答案</div>
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          <div class="card-category">工具</div>
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            <div class="card-answer">文档推荐使用JMX、VisualVM或第三方监控工具（如 Prometheus、Grafana）进行性能监控，并结合日志管理（访问日志和错误日志）来分析问题。</div>
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          <div class="card-source">来源: 10. 监控和调试</div>
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